


Child Swap

by dragonwings948



Category: Doctor Who, Doctor Who (1963), Doctor Who (2005)
Genre: Family, Feels, Fluff, Friendship, Humor, Memories, Reunions, Team as Family
Language: English
Status: Completed
Published: 2020-02-13
Updated: 2020-03-25
Packaged: 2021-02-28 04:28:27
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 5
Words: 3,899
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/22687756
Author URL: https://archiveofourown.org/users/dragonwings948/pseuds/dragonwings948
Summary: The Thirteenth Doctor’s TARDIS is going haywire without reason, and things get even weirder when she comes face to face with friends from her past. Meanwhile, the Fifth Doctor tries to calm his own TARDIS when three strangers appear in the places of Nyssa, Adric, and Tegan.
Relationships: Adric & Fifth Doctor & Tegan Jovanka & Nyssa of Traken, Thirteenth Doctor & Yasmin Khan & Graham O'Brien & Ryan Sinclair
Comments: 38
Kudos: 119





	1. Chapter 1

**Author's Note:**

> I’ve had this idea for quite a while, but only just recently put it down on paper. I’m having way too much fun with this XD

“Everything’s fine!” the Doctor said, trying very hard not to sound like she was panicking. 

Ryan, Graham, and Yaz—all grabbing hold of something in the console room as it rocked violently—looked at the Doctor like they knew she was lying. 

“Totally fine,” she reiterated, trying to reassure herself. She ran madly around the console, trying to rectify the problem...whatever the problem was. Sparks flew, singeing her fingers. She jumped back with a yelp. 

“What’s happening?” Graham asked, yelling over the sound of the cloister bell booming and the engines making a sickly, cacophonous noise. 

“It’s, er…” The Doctor tried to understand the readings, but they were all over the place, spiralling out of control. 

“You don’t know?” Ryan yelled, an edge of panic starting to creep into his voice. 

The Doctor paused to frown at him. “Well give me a minute!” 

“We’ve given you at least five!” Graham protested. 

There was an especially big bump and a collective yell that followed. The engines began to grate with an ear-piercing noise, rising to a crescendo. 

“Hold on,” Yaz said, staring down at her feet. “I feel...weird.” 

“Yeah,” Ryan agreed, “sort of tingly?” 

The Doctor glanced over herself. “I don’t feel any—” But when she glanced back up again, her friends were gone. 

And three others stood in their places. 

* * *

“Don’t worry, everything is fine.” The Doctor smiled at his companions, trying to convince them (and himself) that he wasn’t panicking. 

Nyssa, Adric, and Tegan—all holding tight to the edge of the console as everything turned sideways—didn’t look like they were convinced. Especially Tegan. 

“Completely fine,” the Doctor assured. He pressed a few buttons to look like he knew what he was doing and sparks shot at his face. He leaped back with a startled cry. 

“What’s wrong with the TARDIS?” Adric called over the sounds of TARDIS machinery going haywire. 

The Doctor cleared his throat, mentally willing the TARDIS to give him something,  _ anything  _ to go on. “It’s a, er...time…” 

“You don’t know,” Tegan finished, her voice saturated with biting sarcasm. 

The Doctor huffed. “Now give me just a minute, and—”

“You’ve already had at least five!” Tegan shot back. 

The biggest bump of them all threw both the Doctor and his companions off their feet. The TARDIS engines grated, but with an unusual rattling noise that made the Doctor’s ears ring as it grew louder. 

As Nyssa began to right herself, she frowned and looked down at her hands. “I feel...strange.” 

Adric wiggled his fingers. “Yes, sort of like a tingling feeling.” 

The Doctor glanced down at his own hands. “Well I don’t feel any—” But when he looked up, Adric, Nyssa, and Tegan were gone. 

And three others stood where they had been just a moment ago. 


	2. Chapter 2

**Notes for the Chapter:**

> Sorry this chapter took longer to post; I had so much to do last week that the days just passed by in a blur! 
> 
> Thank you for everyone who’s shown their love for this fic so far; I really love seeing your comments! :)

The Doctor stared. The TARDIS continued to pitch and whine, but now everything else seemed secondary to what was right in front of her. 

“Where are we?” Tegan Jovanka asked, her eyes roaming around the console room. “Why is it so dark?” 

Adric reached out to touch one of the crystal growths. “It looks similar to the TARDIS, only modified.” 

Nyssa of Traken, only a few feet away from the Doctor, looked right into the time lord’s eyes, her lips set in a puzzled frown. The Doctor inched forward a couple of steps, reached out her hand, and lightly touched Nyssa’s temple. The telepathic nudge was gentle, simply affirming who she was. 

Nyssa gasped and stumbled back into Adric. He grabbed her before she could fall and Tegan rushed to her side. 

“Doctor,” Nyssa breathed. 

Tegan spun, as if only just now seeing the Doctor. “Yeah, what did you do to the Doctor?” 

The Doctor held her hands in front of her, having forgotten what it was like to be on the receiving end of that glare. “Tegan, I need you to calm down and listen to me.” 

_“Calm?”_ Tegan shouted. As if spurred by her outburst, a shower of sparks spewed from the console, making the Doctor and Tegan shield their faces as the closest ones to the attack. A violent shuddering followed which threw them all to the ground. 

The Doctor was forced to recall the crisis at hand and pulled herself to her feet. She glanced over to make sure the others were unharmed, and then focused on her task. 

“Right,” she said, “it’s time to figure out what’s going on here.” 

* * *

The Doctor could barely feel the TARDIS shaking because he was staring so hard at the strangers in front of him. 

“Where are we?” an older man asked, squinting. “It’s so bright.” 

The young woman beside him seemed to be very aware and alert for having just appeared out of nowhere. Her eyes honed in on the time rotor. “It’s sort of like the TARDIS console...only a bit different.” 

“This _is_ the TARDIS,” the Doctor said. The room tilted to the side a little and he added under his breath, “...though I’m not sure for how much longer.” 

“Okay,” the old man replied, stepping forward, “so how did you change it, and what did you do with the Doc?” 

The boy who had been silent so far matched the old man’s advancing steps. “Yeah,” he echoed, “bring her back!” 

The Doctor saw determination in all three pairs of eyes. He held up his hands in innocence. “Look, there’s obviously some big misunderstanding—”

The console room slanted fully sideways and all four occupants hit the ground and slid across the open space. The room righted itself after a moment, though not in time to prevent the three strangers from becoming a pile of tangled limbs. Using his grip on the console to his advantage, the Doctor pulled himself to his feet and frowned at the controls. 

“Now it’s time to find out what’s really going on here,” he muttered to himself. 

**Notes for the Chapter:**

> If you enjoy my writing on here, please consider checking out my new website (link in my bio)! I’m trying to really start my writing career this year and I’m coming out with my first fiction book in the next few months! If you just want to read my fics, no judgment at all. XD I really appreciate all the support from everyone on here! While I am focusing more on original writing right now, I won’t abandon the projects I have on here! 
> 
> Thanks for reading my random interruption, you may return to your normal everyday activities. :)


	3. Chapter 3

“Let us go!” Tegan cried, confronting the Doctor with her hands balled into fists at her sides. 

The Doctor grit her teeth, trying to focus. The readings on the console were becoming legible, but they didn’t look good. “Ask Nyssa. She’ll explain.” 

“And how do you know our names?” Tegan continued, entirely ignoring the Doctor’s statement. 

The Doctor got a fix on the readings and saw that another wave of turbulence was coming. “Hold onto something!” 

The TARDIS shook as the Doctor tried hard to steer away from whatever had a grip on her ship. 

“That feels like temporal disturbance,” Adric said, still keeping a hold on Nyssa. 

“It is. It looks like…” She pressed her lips together, not too keen on finding out who would want to do this. “Someone is trying to remotely time ram my TARDIS with another one.” 

“What does that mean?” Tegan asked as she hugged one of the crystal arches. 

“So this  _ is  _ the TARDIS,” Adric said, almost simultaneously. 

Nyssa finally straightened herself up. “Of course it is. She’s the Doctor.” 

Three pairs of eyes stared at the time lord. She paused in her work to look over and smile at them. “Same as always, right? Crashing TARDIS and no explanations?”

“But that’s impossible,” Adric breathed. 

“It’s not. We all saw the Doctor change before.” 

Tegan released her hold on the orange crystal and crossed her arms over her chest, frowning tremendously. “Well I won’t believe it until I have some proof.” Almost immediately she was thrown off balance as the TARDIS careened to the side and she grabbed onto the arch again. 

“You better start believing, Tegan,” the Doctor said, “because I’m going to need you to trust me.” 

* * *

“Tell us where we are,” the woman demanded with unquestionable authority in her tone. 

The Doctor sighed, trying not to get distracted. If he was reading it right, this was not a good situation. “I’ll explain later,” he said. 

“Wait a minute,” the old man began, “remember the Doc said she used to be a man?” 

“I didn’t think she was actually serious,” the woman said. 

“And didn’t she say that she was Scottish?” the boy asked. “She didn’t mention anything about wearing celery.” 

The Doctor touched the celery on his lapel. “It actually is very useful—”

Another quake rocked the TARDIS. The three strangers helped each other stay upright. 

“Is there some kind of weird time thing going on?” the boy asked. “Is that how we got here?” 

“It seems like someone has tried to time ram my TARDIS with another.” He glanced up at them sharply. “You said you’ve been in a TARDIS before?” 

“Yeah, the Doctor’s,” the old man replied. 

“I  _ am  _ the Doctor.” 

Three pairs of eyes, wide as saucers, stared at him in stunned silence. 

“Well, that means we must be from the future, doesn’t it?” The man looked to his companions for help. 

The woman didn’t look entirely convinced. “I’m going to need some proof.” 

Sparks flew from the console. “No time, I’m afraid,” the Doctor said. “I’m going to need you to trust me.” 


	4. Chapter 4

“I didn’t think the TARDIS could be controlled remotely,” Nyssa said, coming to stand at the Doctor’s side. 

The Doctor grinned and pointed at her. “Ten points to Nyssa! You’re right, the TARDIS usually can’t be controlled from the outside. Only the time lords can, in theory.”

“So it’s the time lords?” asked Adric. 

“Probably. Maybe. I can’t really tell.” She rapped her knuckles against the console and squinted at the readings. Everything was jumbled as the TARDIS tried to fight against the mysterious controller. 

Tegan scoffed, still keeping her distance from the console. “Now you’re starting to sound like the Doctor.” 

“You said we had to trust you.” Adric stood on her other side and leaned over her shoulder, as if trying to make sense of the readings himself. 

“Getting to that bit.” The Doctor took a deep breath as the half-formed plan solidified itself in her mind. She straightened up and locked gazes with all three of her old friends. “We’re going to time ram my TARDIS. Sort of.” 

There was a moment of silence, broken only by the whining sounds of the TARDIS engines resisting the time ram. 

“I thought that was what we didn’t want!” Tegan exclaimed. 

“Exactly. It’s the last thing they’ll expect us to do.”

“Isn’t there some way to escape?” Nyssa asked. 

Giving it one last try, the Doctor flipped the switch that should have freed them from whatever force was holding the TARDIS. Instead of freedom, however, all that resulted was a churning, grating sound. The floor shook like an earthquake was beginning. 

“Nope!” 

Adric looked at her, eyebrows raised. “What do you need us to do?” 

The Doctor smiled, her hearts warming at his faith in her. She took a step back, talking to Nyssa and Adric as the ones who were closest. “The TARDIS has safeguards against being time rammed; that’s why all of this is happening,” she began, talking with her hands. “I need all three of you to help me take down the safeguards. It would take some time for only one person and we have about—er, two minutes?” 

Nyssa immediately placed her hands on the console and the Doctor began to instruct her on what her job was. Meanwhile, Adric tried to pry Tegan away from the crystal arch. 

“Let go of me! I’m not going to help get us all killed!” 

Adric looked to the Doctor for help. She rushed over and looked right into Tegan’s eyes. “If you don’t help us, then it _will_ get us all killed.” 

Her eyes widened. “You mean—you have a plan?” 

The Doctor flashed a grin. “When don’t I?” She squeezed Tegan’s shoulder. “Brave heart, Tegan. I’m going to need you to make a very important call to another TARDIS…” 

* * *

“The TARDIS can be controlled?” the woman asked the Doctor. 

“Not normally, er…” He suddenly realised that he didn’t know their names. 

“Yaz,” she introduced herself. “Ryan and Graham,” she added, pointing to the boy and the older man in turn. 

The Doctor nodded. “Lovely to meet you all, though I do wish it were under different circumstances.” He winced as the console room jerked. “And to answer your question, it normally can’t be controlled, but sometimes the time lords like to force me to do their dirty work.” 

“Eh?” asked Graham, stepping forward. “The time lords? You mean the Doc’s people? _Your_ people?” 

The Doctor shook his head. “It’s not important. I can’t tell who’s controlling the TARDIS now, but if we don’t do something soon—” The console room shuddered and the Doctor raised his voice. “I’m very much afraid that we’ll be destroyed along with the TARDIS in a time ram!” 

“What _is_ a time ram?” Ryan asked. 

The Doctor was at a loss. He knew he couldn’t escape, so there was only one thing for it. “Something you’re about to become very familiar with...” He threw a switch, lowering the TARDIS’ defences, and the shaking calmed a little. “...because we’re about to do it.” 

The booming of the cloister bell was the only thing to break the silence that followed.

“Didn’t you just say that would get us killed?” Graham asked. 

The Doctor began making preliminary preparations. “Yes. We’re going to shut off all the safeguards; that’s why the TARDIS has gone haywire. She’s programmed not to be able to time ram.” He pulled another lever and the cloister bell became silent. 

“If you’re the Doctor,” Yaz reasoned, “then you have a plan.” 

“So what do you need us to do?” asked Ryan. 

The Doctor looked up, surprised at their instant trust. They really must know him in the future. 

“Yaz, come over here,” he instructed, singling her out as the most capable of the three. He showed her how to set the coordinates and emphasised how important it was to get it exactly right. Next he demonstrated Ryan’s job, explaining how he needed to make sure all of the TARDIS safeguards were down and shut them off if they decided to turn back on of their own accord. Finally, he instructed Graham, “Press this button, but only when I tell you to.” 

“Oi, why am I the one who just presses a button?” 

“It’s a very important button,” the Doctor said. 

Ryan snickered. “Sure you can handle it, Granddad?”

“Don’t cramp up,” Yaz teased. 

“Thanks for the backup, you two,” he grumbled. 

An incessant beeping started up from the console, though not related to the trouble at hand. The Doctor stared at the console in confusion for a moment. 

“What’s that?” asked Yaz. 

“We’re receiving a transmission.” He answered it and watched someone who was both familiar and a complete stranger appear on the scanner. 


	5. Chapter 5

**Notes for the Chapter:**

> Sorry this is late, but the world is crazy right now. Speaking of, I hope you all are doing okay!! I'm going to try and put out some more content in the next week or two (or three or four) to try and lift some spirits (including mine)! 
> 
> Thanks for all the love for this fic! :D You guys rock!

“Contacting the Doctor!” The Doctor’s younger self appeared, his face projected onto the wall of the TARDIS. The Doctor grinned. “Aw, look at you with your celery!” 

“Doctor!” Tegan yelled with relief. 

“Doctor!” Graham appeared on the screen next to the celery-wearing Doctor. “Thank God you’re here!” 

“Graham, the button!” Yaz’s voice called from off the screen. 

Graham disappeared, leaving only the Doctor. “So  _ you’re _ my future self?” 

“That’s right!” The Doctor grinned and pushed her hair behind her ear. “Seems to have been a mixup with our companions; I think it might have been the TARDIS trying to protect them--”

“--but she was under so much strain that instead of putting them on the nearest safe planet, she simply transported them in time to another version of herself.” 

“The TARDIS: safest place in the world, except when you’re being time rammed.” 

The younger Doctor turned to the side and said something quietly to Yaz. After a moment he looked back to the screen. “Any idea who’s doing this?” 

The Doctor shrugged. “Several ideas, but no facts. And what exactly are you doing?” She stood on her toes, wishing that she could get a better view of her friends in the old console room. 

“I’m materialising my TARDIS inside of yours, of course.” He pushed several buttons in quick succession. “And the calculations are very precise, so if you wouldn’t mind…”

“Wait!” The Doctor darted toward the screen.  _ “I’m  _ materialising inside of  _ your  _ TARDIS. If we both do it, we  _ will  _ get caught in a time ram!” 

The younger Doctor seemed unconcerned. “Then you stop and I’ll come to you.” 

The Doctor paused and frowned, thinking for a moment. Precious seconds of silence ticked by. “Like you said, the measurements are very precise. One wrong number, one decimal point out of place, and we’ll destroy ourselves and leave a massive paradox in our place. I’ve had hundreds of years more experience; best leave it to me.” 

Celery-Doctor’s eyes narrowed and he stopped his work at the console to look directly at the screen. “You’ll remember,” he retorted, “that I  _ have  _ done this a few times before.” 

The Doctor yelled in frustration, spinning to face Adric, Tegan, and Nyssa. “Argh! Why am I so stubborn?” 

“A little faith in myself would be nice,” came the voice behind her. 

“Hey.” Ryan’s voice made the Doctor turn back to the screen. “You can trust  _ us,  _ Doctor.” 

“Yeah.” Yaz appeared beside him. “You’ve saved us before; now it’s our turn.” 

Graham spoke up: “You just hang tight, Doc! See you soon!” 

The young Doctor met her eyes. She took a step back from the screen. “All right,” she said quietly. “See you in a minute, fam!” Lower, she added: “Keep them safe.” 

“Of course I will.” 

The connection cut. The Doctor took a deep breath, trying to calm the anxiety rising within her. “Time ram is off, gang!” 

“Are you sure the Doctor can do it?” asked Tegan. “He can’t even make it to Heathrow!” 

The Doctor looked at her three companions. “I trust him, and I trust my friends. You should, too.” 

“What do we do now?” Nyssa asked. 

The Doctor pressed her lips together. She wished there was something she could do to occupy her mind from nagging worry, but there was only one thing for it. “Wait. All we can do is wait.” 

* * *

“Ready?” the Doctor asked. He looked each of the three new acquaintances in the eye, feeling his confidence in them boosted now that he knew his future self trusted them so much. 

They all nodded. “Born ready,” Ryan said, excitement shining in his eyes. The Doctor noted that none of them looked scared. 

“Here goes nothing.” The Doctor took a deep breath and finished breaking down the TARDIS safeguards. “Ryan, get ready!” 

Ryan pressed a few buttons and pulled a lever, whooping with excitement as the TARDIS pitched forward. “Our Doctor would never let us do this!” Ryan said with a grin. 

“Concentrate, Ryan!” Yaz admonished. “Remember, the Doctor said if we get one thing wrong, it’s all over.” 

“Thanks for the encouragement,” Graham said, his hand hovering over the button. 

The Doctor watched their progress and smiled.  _ This might actually work.  _ “Right, Graham-- _ now!”  _

Graham slammed his hand down on the button. The time rotor went up and down and the TARDIS engines grated louder than normal. There was a definitive thump. All was silent. 

“Did we do it?” Graham whispered. 

Ryan shrugged. “We’re not dead.”

“Did it work?” Yaz echoed, looking over at the Doctor. 

He fired up the scanner. A dark room with bright orange and blue lighting appeared on the screen. “Does that look familiar?” 

“The TARDIS!” Yaz exclaimed. 

“We did it!” Ryan pumped his fist. 

“All right we got there,” began Graham, “but what about whoever started this in the first place?” 

“Yes, I’d very much like to know who tried to kill me. It seems that for now they’ve let us go, or we’ve given them the slip. We were only a centimetre away from time ramming into each other anyway, so they likely thought we were giving in.” 

The TARDIS door opened and Nyssa and Adric rushed in, followed by Tegan. “Doctor!” they exclaimed. 

Tegan frowned at Ryan, Graham, and Yaz. “Hey, did you replace us?” 

The future Doctor pushed through, hands in her coat pockets. “These three are mine, actually!” She looked around the bright console room with a small smile, nodding. “Ah, the minimalist days. Kinda miss it!” 

“Doctor!” Ryan, Graham, and Yaz joined her in a hurry, all smiles. 

“Did you see that?” asked Ryan, his voice pitched high with exhilaration. “We totally stopped the time ram! We were flying the TARDIS!” 

“Well, actually--” the younger Doctor began. 

But just then there was a shift in the ground. The Doctor met the eyes of his future self and followed on her heels as she ran back into her console room. The Doctor took a moment to examine the dark, ethereal atmosphere. 

“I don’t really like what you’ve done with it.” 

The Doctor rolled her eyes, already working at the console. “Don’t start. Look!” She pointed at a set of readings. “We’re being moved!” 

The questions “Where?” and “How?” resounded from the group of six companions that had followed their Doctors into the console room. 

“Ah, Doctors.” 

Both Doctors froze at the sound of the voice that resounded around the room. 

“How wonderful to have you together with all of your little friends.” 

“No,” Nyssa whispered. 

“That’s not…” Tegan said, her voice quavering with fear. 

But before their worst fear could be truly realised, the TARDIS landed with a thump. The Doctor’s TARDIS closed its doors, and the future Doctor’s console room began pumping out acrid smoke. Fits of coughing started up. 

“Out!” the future Doctor yelled, her sleeve over her mouth. “Everyone out!” 

The Doctor coughed to clear his throat before he was able to say: “I can’t leave my TARDIS in here for long.” 

Yaz rattled the locked door of his TARDIS. “It doesn’t look like you’re getting back in anytime soon.” 

“We’ll worry about that--” The Doctor’s last word was choked off and she began ushering everyone toward the TARDIS doors. 

As soon as they all exited, the doors shut with a ring of finality. Graham immediately collapsed onto his knees, coughing violently. The rest of the companions surrounded him, making sure he was okay. 

The Doctor gazed out at the ocean, feeling his shoes sinking into the soft sand they were standing on. “Somewhere in Scotland, I think,” he said. 

His older self bent over and scooped up some sand in her hand. She sprinkled a bit on her tongue, chewed thoughtfully, and nodded. “Definitely. Outer Hebrides.” 

The Doctor frowned at her. 

Graham finally stood, leaning on Ryan. “What was that voice we heard?” he asked. 

“The Master,” Nyssa said softly, her eyes downcast. 

“Didn’t sound like him.” Ryan looked to his Doctor. 

“If he’s a time lord too…” Yaz muttered. 

“It was the Master controlling us all along?” Tegan asked. 

The Doctor sighed. “It wouldn’t surprise me.” 

“So what do we do now?” Adric asked. 

The waves crashed against the shore. Everyone looked to their Doctor, no doubt expecting a brilliant plan. 

“Right,” the older Doctor began, walking through the group, “now that we all know we can trust each other, we should have no problem figuring out what to do while our TARDISes clear out.” 

“What about the Master?” Tegan asked. 

The younger Doctor smiled, looking to his future self. “We’ve beaten him before, and this time we have double the help. Isn’t that right, Doctor?” 

The Doctor grinned. “You bet, Doctor.” 


End file.
